Microsoft and Open Whisper Systems (makers of the Signal app) surprised many on Thursday when they said they are partnering to bring support for end-to-end (E2E) encrypted conversations to Skype. From a report: The new feature, called Skype Private Conversations has been rolled out for initial tests with Skype Insider builds. Private Conversations will encrypt Skype audio calls and text messages. Images, audio or video files sent via Skype’s text messaging feature will also be encrypted. Microsoft will be using the Signal open-source protocol to encrypt these communications. This is the same end-to-end encryption protocol used by Facebook for WhatsApp and Facebook Messenger, and by Google for the Allo app.